US 6,633,936 B1 · Adaptive retry mechanism

Abstract

An adaptive retry mechanism may record latencies of recent transactions (e.g. the first data transfer latency), and may select a retry latency from two or more retry latencies. The retry latency may be used for a transaction, and may specify a point in time during the transaction at which the transaction is retried if the first data transfer has not yet occurred. In one implementation, the set of retry latencies includes a minimum retry latency, a nominal retry latency, and a maximum retry latency. The nominal retry latency may be set slightly greater than the expected latency of transactions in the system. The minimum retry latency may be less than the nominal retry latency and the maximum retry latency may be greater than the nominal retry latency. If latencies greater than the nominal retry latency but less than the maximum retry latency are being experienced, the maximum retry latency may be selected. On the other hand, if latencies greater than the maximum retry latency are being experienced, the minimum retry latency may be selected.

Claims68

Dependent claims

A method comprising:

establishing a plurality of retry latencies;
determining latencies of transactions on a bus, each latency representing a time period from a first event of a corresponding transaction to a second event of said corresponding transaction;
and
selecting a first retry latency for a first transaction from said plurality of retry latencies responsive to latencies of N previous transactions, wherein N is a positive integer, said first retry latency indicative of a point in time, measured from said first event of said first transaction on said bus, that said first transaction is retried on said bus if said second event of said first transaction does not occur before said point in time.

1 more element

A carrier medium comprising a database which is operated upon by a program executable on a computer system, the program operating on the database to perform a portion of a process to fabricate an integrated circuit including circuitry described by the database, the circuitry described in the database including:

a buffer configured to store latencies of transactions on a bus, each of said latencies representing a period of time from a first event of a corresponding transaction to a second event of said corresponding transaction;
and
a circuit configured to select a first retry latency for a first transaction from a plurality of retry latencies responsive to latencies of N previous transactions from said buffer, wherein N is a positive integer, and wherein said plurality of retry latencies are established separate from said latencies in said buffer, said first retry latency indicative of a point in time, measured from said first event of said first transaction on said bus, that said first transaction is retried on said bus if said second event of said first transaction does not occur before said point in time.

Dependencies are inferred from the claim text.

Adaptive retry mechanism

Life of this patent

Adaptive retry mechanism

Life of this patent

Abstract

Claims68